Pressure compensation label for sticking to a surface, and method

ABSTRACT

A pressure compensation label for sticking to a surface, provided with a pressure compensation opening, of a housing or some other article, has a first film for sticking to a surface provided with a pressure compensation opening, and an outer, second film and also an air-permeable membrane film which is arranged between the first film and the second film. The first film has a cutout, intended for positioning over a pressure compensation opening, and a number of ventilation ducts. Each of the ventilation ducts is separated from the cutout by a film region of the first film. The membrane film covers the cutout and each of the film regions between the cutout and the number of ventilation ducts. The outer, second film extends laterally beyond the membrane film, at least regionally covers the number of ventilation ducts of the first film laterally outside the membrane film, and spans a ventilation path which leads from that surface of the membrane film that faces the second film to the number of ventilation ducts in the first film.

The application relates to a pressure compensation label for adhesiveaffixation to a surface of a housing or another article, which surfaceis provided with a pressure compensation opening. The applicationfurthermore relates to a method for the production of pressurecompensation labels.

The most varied systems, devices, components or individual parts inmechanical engineering, in automotive construction or in other areas ofapplication possess pressure compensation openings. Housings or outerhousings, above all, are often provided with one or more pressurecompensation openings. In the case of devices that are operated attemperatures that vary over different times of day or different seasons,or devices that themselves produce heat because of their powerconsumption, pressure compensation openings are necessary, for example,so that the air situated in the device housing can expand as necessary,depending on the operating temperature, or can partly leave the housing,or so that air can flow back into the housing when it cools.

Particularly in components that are installed in motor vehicles or othermeans of transport for controlling vehicle parameters, the electronicsinherent in the component produce heat, which heats not only thecomponent and its housing, but also the air enclosed therein. Withoutpressure compensation, excess pressure would occur in the housing of theelectronic component, relative to the outside surroundings, whichpressure can reach up to 300, 500 or even 700 mbar, depending on theambient temperature, intensity of use, and electric power consumption ofthe electronic component during its operation. Similar problems ofpressure compensation can occur, other than in automobile construction,also in other machines, industrial systems or devices. Housings ofelectronic components are therefore often provided with pressurecompensation openings, for example in the form of boreholes or otherpassages in the housing wall.

Such pressure compensation openings do not remain exposed or exposed,but rather are covered in such a manner that pressure compensation bymeans of gas exchange continues to be possible, but wetness or moistureand water cannot penetrate into the housing of the component. Aside fromsolid, three-dimensionally formed closures for pressure compensationopenings, closures in the form of pressure compensation labels areparticularly used; these can be produced from foils/films and aretherefore relative cost-advantageous. But label-like pressurecompensation closures must also be robust enough to withstand weatheringinfluences and other mechanical stresses, in particular the forces thatoccur when using steam-jet degreasers or high-pressure washers. Suchconditions of use have required a rather complex structure of pressurecompensation labels until now, in which structure support structuresbetween the foils/films can also be required in addition to foils/filmsand adhesive layers.

It is the task of the present invention to make available a pressurecompensation label that has the simplest possible structure, can beproduced in the simplest possible manner, and is therefore inexpensive,which label is mechanically very stable and resistant to externalmechanical stresses. Furthermore, a method is supposed to be madeavailable, with which method mechanically resistant pressurecompensation labels can be produced in simple and cost-advantageousmanner. This task is accomplished by means of the object of claims 1 and13.

The pressure compensation label according to claim 1 possesses a lower,first film and an outer, second film disposed above the latter orfurther up, as well as a membrane film. According to this application,the membrane film is disposed between the first film and the secondfilm. The membrane film is gas-permeable and particularly air-permeable,but impermeable for moisture and water or other liquids. The membranefilm is a thin layer composed of a suitable membrane material; for thispurpose, any conventional membrane film can be used. The first filmdisposed underneath the membrane, the underside of which film is to beadhesively affixed or is adhesively affixed to the surface of thedevice, of the electronic component or of the housing, possesses arecess—in practical manner, in its center—that is to be positionedprecisely above the pressure compensation opening of the device or ofthe housing. This recess in the lower, first film forms the device-sideaccess to the underside of the membrane film of the pressurecompensation label. The first film is otherwise adhesively affixed ontothe housing wall of the device or of the electronic component with itsunderside or by means of an underside adhesive layer, specifically inthe immediate vicinity of the pressure compensation opening to be sealedoff. A circular-ring-shaped or circular-disk-shaped surface region ofthe housing has the pressure compensation label adhesively affixed toit, for example, wherein the pressure compensation label also covers thepressure equalization opening itself, of course, specifically with themembrane film and also with the outer, i.e. upper second film. The firstand the second film are, in particular, plastic films.

The first film and the second film extend laterally beyond the membranefilm; in particular, their edge regions can run completely around themembrane film, laterally outside of the membrane film.

It is provided that the first film also has a number of ventilationchannels in addition to the recess for the pressure compensationopening. These channels are worked into the first film or are anintegral part of it. Furthermore, it is provided that each of theventilation channels in the first film is separated from the recess forthe pressure compensation opening by a respective film region of thefirst film. Therefore separation regions exist between the centralrecess above the pressure compensation opening and the ventilationchannels in the first film, which regions block a direct connectionbetween the central recess and the ventilation channels, as materialbars or material bridges in the film plane. These film regions do notneed to be configured or reinforced in any particular manner, but ratherare merely film regions of the first film that have remained intact, inother words have not been punched out or weakened or machined in someother way. While the recess and the ventilation channels in the firstfilm can be implemented as punched-out parts of the first film, the filmregions made available for their separation represent intact bridgeregions between the recess and the ventilation channel or theventilation channels, for example, which regions have not been machinedby means of punching or other effects.

In the case of this film structure of a pressure compensation label, inwhich the membrane film is disposed above the first film, i.e. betweenthe first and the second film, a person skilled in the art would usuallyconfigure the further ventilation path at a level above the membranefilm or at least above the first film, because when the housing heatsup, the enclosed air, which reaches the membrane film through thepressure compensation opening of the housing and the recess of the firstfilm, exits from the membrane film on its top. According to thisapplication, however, the further ventilation path is passed back intothe plane of the lower, first film, i.e. down into the plane of thefirst film 1, which is to be adhesively affixed onto or has beenadhesively affixed directly onto the housing of the electronic componentor the other device. As a result of this positioning of the ventilationchannels or further recesses, the first film, which is responsible fordirect adhesion of the pressure compensation label to the housing, mighttend to look structurally rather weakened in a top view, and thereforethe introduction of ventilation channels into the first, lowermost film,of all things, might appear to be absurd, at first glance. However, inthis method of construction—in connection with further characteristicsthat will be explained below—a mechanically robust overall structure ofthe pressure compensation label can be achieved, in particularly simplemanner, particularly since the first film is held in shape both duringlabel production and after dispensing of the pressure compensationlabel, on both sides, by the adjacent material surfaces, and furthermoreitself offers a greatly enlarged, almost full-area adhesive surface.

First of all, it is provided that the membrane film covers the recess aswell as the film regions between the recess and each of the ventilationchannels. For example, the recess for the pressure compensation openingand its entire edging are covered by the membrane film, and therebysealed in moisture-sealed manner. Furthermore, it is provided that theouter film, i.e. the second film, extends laterally beyond the membranefilm, that the second film covers the number of ventilation channels ofthe first film laterally outside of the membrane film, at least incertain regions, and that the second film furthermore spans aventilation path that leads from the surface of the membrane film thatfaces the second film all the way to the number of ventilation channelsof the first film. If the air in a housing to which the pressurecompensation label described here is adhesively affixed therefore heatsup, it first passes through the membrane film before reaching theventilation channels, as it passes through the label.

Because of the fact that the second film (just like the first film)extends laterally beyond the membrane film, the further ventilation pathtoward the outside can be structured solely using the first and secondfilm, thanks to the ventilation channels introduced into the first film.Actually, additional layers for the channels or at least elevatedadhesive dots would have to be provided between the two films, so thatthe air can escape to the outside between them or can flow in again.Particularly in the outer region—close to the circumference of thepressure compensation label—additional films, adhesive dots, materiallayers or other structures with embedded channels would actually have tobe configured in order to implement the ventilation path from themembrane top or its center to the outside, i.e. toward the surroundingsof the label.

However, because the first film already carries a number of ventilationchannels within it according to this application, such additionaladhesive dots, film layers or structures can be eliminated withoutreplacement. In regions laterally outside of the membrane film, thesecond film serves as a top cover for the ventilation channels; it isadhesively affixed to the first film, specifically over the full area,if at all possible. The gaps of the first film—with the exception oftheir inner, if necessary also their outer channel ends—are covered bythe second film and form the ventilation channels to the outside. Inorder not to interrupt the ventilation path between the membrane top andthe channel openings, it is sufficient if the first and the second filmdo not lie directly one on top of the other at least on a narrow regionaround the membrane film, but rather possess a certain distance from oneanother. Otherwise, no further structures for channel guidance arerequired in the ring-shaped outer region of the pressure compensationlabel, i.e. laterally outside of the membrane film.

Depending on the embodiment, further structures for widening theventilation path between the inner end of the respective ventilationchannel and the membrane top can otherwise be provided.

The pressure compensation label described here first of all possesses nocover of the ventilation channels from below, but rather makes use ofthe circumstance that after the label is dispensed, the housing surfaceitself encloses the first film from below. In the case of conventionalpressure compensation labels, if they carry ventilation channels inthem, the ventilation channels are already worked into the label infinished form, i.e. delimited both upward (in the direction away fromthe housing surface) and also downward (in the direction toward thehousing surface). In the case of a pressure compensation label accordingto this application, in contrast, the underside delimitations of theventilation channels are only “formed” when the label is dispensed ontothe device surface or housing surface.

In the case of the label described here, the second film lies directlyon the first film, over a large area, laterally outside of the membrane.As a result of this large-area contact surface region, within which thefirst and the second film border on one another directly or areseparated at most by an adhesive layer that lies between them, thepressure compensation label is particularly stable and mechanicallyresistant to external mechanical stresses, including pressure forces andshear forces. Furthermore, the label makes do with fewer films or othercomponents, and can therefore be produced in particularly simple andcost-advantageous manner.

The ventilation channels ensure lateral offset of the respective outeropening in the label and the membrane top, in order to protect thesefrom destruction by high-pressure washers or steam-jet degreasers, orfrom other stresses and/or contaminants. Depending on the embodiment,the ventilation channels of the first film can optionally lead to theoutside at the outer edge of the first film or—if the outer channel enddoes not reach all the way to the film edge—can lead to the outsidethrough channel exit openings of the second film.

Some exemplary embodiments will be described below, with reference tothe figures. These show:

FIGS. 1A to 1C, exemplary embodiment patterns of the lower, first filmof a pressure compensation label,

FIGS. 2A to 2C, exemplary cutouts of a membrane film on the first filmfrom FIGS. 1A to 1C,

FIGS. 3A to 3B, schematic top views of the outer, second film of apressure compensation label, based on FIG. 1A and 2A, respectively,

FIGS. 4A and 4B, alternative exemplary embodiments with regard to thechannel exit openings of the second film in FIG. 3A,

FIGS. 5A and 5B, schematic cross-sectional views of pressurecompensation labels, for exampled based on FIG. 3A,

FIGS. 6A and 6B, two exemplary embodiments having an additional,air-permeable layer as a spacer on the membrane film,

FIG. 7, a schematic cross-sectional view relating to an embodimentsimilar to that of FIG. 6A or 6B,

FIGS. 8A and 8B, two modified exemplary embodiments with regard to theshape of the second film,

FIG. 9 a schematic top view of the second film from FIG. 8B,

FIG. 10 an article provided with a pressure compensation label,

FIG. 11 a further embodiment of a pressure compensation label,

FIG. 12 an alternative embodiment to FIG. 9,

FIG. 13 an alternative embodiment to FIG. 2C,

FIG. 14 a supplemental schematic view relating to FIG. 2A, with theadditional representation of the contact surface region and its inneredge,

FIG. 15 an alternative embodiment to FIGS. 2A and 14, with a membranefilm that overhangs the inner ends of the ventilation channels,

FIG. 16 a supplemental schematic view relating to FIG. 2B, with theadditional representation of the contact surface region and its inneredge,

FIG. 17 an alternative embodiment to FIGS. 2B and 16, with a membranefilm that overhangs the inner ends of the ventilation channels, and

FIG. 18 a schematic representation of an exemplary method for theproduction of pressure compensation labels.

FIGS. 1A to 1C show some exemplary embodiment patterns for the lower (orinner, i.e. to be adhesively affixed directly to the surface of thedevice or housing) first film of the pressure compensation label. Theviews of the first film 1 shown in FIGS. 1A to 1C can be implemented,for example, as a cut pattern or punched pattern; in particular, anumber of ventilation channels in the form of gaps or recesses can beconfigured outside of the central passage openings, above all aspunched-out parts of the first film. The height of the ventilationchannels then corresponds to the layer thickness dl of the first film(cf. FIGS. 5A and 5B). However, the ventilation channels in the firstfilm can alternatively be configured also as weakened film regions,particularly thinned in comparison with the remaining film thickness. Inthe simplest case, however, the first film is simply punched out in theregion of the recess for the pressure compensation opening and also inthe region of the ventilation channels, i.e. provided with acorresponding inner opening.

FIG. 1A shows a first exemplary embodiment, in which the first film 1,which is shown in square shape here, has a centrally disposed recess 6,which comes into coverage with the pressure compensation opening of ahousing surface when the finished pressure compensation label 10 (FIGS.5A and 5B) is adhesively affixed to this surface. The pressurecompensation opening of a housing of an electronic component or of anelectronic device is generally circular in its layout; the samepreferably holds true for the recess 6 of the first film 1.

The first film 1 additionally has a number of ventilation channels 7;these are preferably elongated and lead from the inside to the outsidein the lateral direction, in each instance, i.e. from a region close tothe recess 6 to an edge region at a distance from the recess 6. Forexample, each ventilation channel 7 runs in a straight line, i.e.linearly; approximately as shown, radially in the direction from thecenter of the first film 1 of the pressure compensation label (or itsrecess 6) all the way to the label edge. Each ventilation channel 7possesses an inner end 11 and an outer end 12. The inner end 11 isseparated from the recess 6, which is provided for the pressurecompensation opening, by means of a film region 8, in each instance.

As will still be described as an example using some of the followingfigures, the inner end of the ventilation channels can optionally becovered with the membrane film or, instead, can be overlaid by thesecond film (at a certain height above the first film).

In the latter case, it is guaranteed by the thickness of the membranefilm, which reaches at least close—for example between 0.5 and 1.0 mm—tothe inner end of each ventilation channel, and, if applicable, also bythe thickness of a spacer above the membrane film, that the second filmspans the inner ends of the ventilation channels at a distance from thefirst film. Therefore the second film does not lie directly on the innerends of the ventilation channels, but rather the further ventilationpath, which leads from the top of the inner ends of the ventilationchannels all the way to the center of the top of the membrane film,which lies higher, is kept clear by means of the distance of the secondfilm from the first film above the inner ends of the ventilationchannels. From there, the air then passes through the air-permeablemembrane film during pressure compensation, and then gets into theinterior of the cooling housing or device, through the central recess ofthe first film and through the pressure compensation opening of thehousing or device, over which the label is adhesively affixed. Incontrast, when a housing or device is heating up, part of the airexpanding in its interior passes through the ventilation path in thepressure compensation label in the opposite direction, and gets to theoutside through the ventilation channels.

In the first case, as well, when the inner end of the ventilationchannels is covered by the membrane, at least in certain regions, thesecond film is at a distance from the first film—now as the result ofthe edge of the membrane film that lies in between; and from the innerends of the ventilation channels, the further ventilation path—throughthe interstice between the outer edge of the membrane film and theunderside of the second film—also runs further to the center of the topof the membrane film.

The ventilation channel 7 or the number of ventilation channels 7therefore does not reach all the way to the central recess 6, but ratherthe latter is completely surrounded by an inner film region of the firstfilm 1, and therefore does not possess any lateral passage to theventilation channels 7 or actually to the outside. The film region thatsurrounds the recess 6 therefore particularly encompasses the filmregions 8 provided for separation from the ventilation channels 7. Thefilm regions 8 therefore serve as barriers or bridge regions, and—justlike the recess 6—have a membrane film 3 adhesively affixed over themand are sealed (cf. FIGS. 2A to 2C). The ventilation channels 7, incontrast, run laterally outside of the membrane film and are thereforedirectly covered by an upper, second film over the major part of theirchannel length.

FIG. 1A simultaneously shows two alternative embodiments with regard tothe outer channel ends 12, depending on where the outer edge of thefirst film 1 runs. In the one embodiment, the outer edge is formed byR1, i.e. it runs outside of and at a distance from the outer end 12 ofthe ventilation channels 7. In this regard, the ventilation channels 7in the first film 1 do not reach all the way to the outer edge R1 of thefilm. In this embodiment, the second film that is to be adhesivelyaffixed later is provided with its own channel exit openings, which cometo lie above the outer channel ends 12 of the ventilation channels 7 ofthe first film 1.

In the alternative embodiment, also according to FIG. 1A, the outer edgeof the first film 1 is formed not by R1, but rather by R1′ (shown with abroken line). In this case, the ventilation channels 7 end at the outeredge or film edge indicated with R1′, i.e. they lead directly to theoutside at the label edge. In this regard, no channel outlet openingsare required any longer in an upper, second film, but rather the outerend 12 of each ventilation channel 7 lies at the outer edge of the firstfilm 1.

The above explanations apply likewise for FIG. 1B, which shows a firstfilm 1 having a circular outer contour, as well as for FIG. 1C, whichshows a first film 1 having an oblong film outline, for example with alateral main expanse. The dimensions shown in all figures of this/theseapplications are merely exemplary and are often shown in enlargedmanner; the proportions are also not to scale. The reference symbolsapply uniformly for all the figures.

In FIG. 1C, in order to avoid repetition, the film outline is only shownfor the embodiment in which the outer ends 12 of the ventilationchannels 7 reach all the way to the outer, i.e. circumference-side filmedge R1′. The first film 1 can have an oval, polygonal or any otherdesired outer outline, for example.

Regardless of the embodiment patterns shown, it is likewise possible toprovide or punch only a single ventilation channel 7 or another numberof ventilation channels 7 in the first film 1.

In FIGS. 1A to 1C, the embodiment pattern with the edge R1′—particularlyas a punched pattern—might not appear to be very stable for the shape ofthe first film 1 at first glance (just like later in FIG. 6A or 6B),because the outer film regions of the first film 1 are only heldtogether by the inner film regions 8 between the recess 6 and theventilation channels 7 that serve as bridge regions. However, the top 1a of the first film 1, shown in FIGS. 1A to 1C, is stabilized by anupper, second film 2 (FIGS. 3A to 4B). Furthermore, the outer regions ofthe first film 1 are already held in position during production of thelabel as a whole, on the underside (and before adhesive affixation ofthe upper, second film, also on the top), by means of a correspondingsupport film—typically silicone-coated or anti-adhesion-coated paper ora silicone-coated or anti-adhesion-coated polymer film—(FIG. 18 andclaims 13 to 15). Even after the finished label as a whole is adhesivelyaffixed, when the first film 1 with its adhesive underside is directlyadhesively affixed to a housing surface (FIGS. 5A, 5B, and 7), the filmregions of the first film 1 that are disposed between the ventilationchannels 7 remain secured to prevent slipping or other deformations,from above and from below.

A membrane film 3, which is shown on the top 1 a of the first film 1 inFIGS. 2A to 2C, is disposed between the first film 1 and the second film2 (not yet shown in FIGS. 1A to 2C). The membrane film 3 covers the top1 a of the first film 1 with its underside, specifically in the regionof the recess 6 and the inner, inner film regions 8 disposed between itand the ventilation channels 7. The ventilation channels 7, in contrast,are not covered by the membrane film 3. Preferably, the first film 1 isadhesive on both sides; this characteristic can be combined inconnection with any desired embodiment according to the figures, claims,or description parts of this application. The membrane film 3 seals therecess 6 off in moisture-tight manner, but is permeable for air andtherefore allows pressure compensation of a housing, with the outsidesurroundings of the housing, at its pressure compensation opening overwhich the label has been adhesively affixed, without moisture being ableto penetrate into the housing interior.

The ventilation path L between the inner ends 11 of the ventilationchannels 7 and of the top of the membrane film 3, which will still beexplained later using FIGS. 3A to 3C, can be expanded in that—as shownas an example in FIGS. 2B and 2C—the shape of the membrane film 3 ismodified relative to a circular or polygonal outline (cf. FIG. 2A).Thus, FIGS. 2B and 2C show that the membrane film 3 can have lateralbulges 21, i.e. projections. Constrictions 22 are present between thebulges 21, where the membrane film 3 possesses a smaller lateral expansethan in the region of the bulges 21. The lateral bulges 21 of themembrane film 3 come into coverage with wing areas (here, quadrants ofthe film surface), which lie, in each instance, between ventilationchannels 7 of the first film 1, which channels are adjacent to oneanother. Accordingly, the constrictions 22 come into coverage with thefilm regions 8 that serve as material bridges and lie between thecentral recess 6 and the ventilation channels 7 of the first film 1, oroverlap with the film regions 8, at least in certain regions. Furthermeasures for expanding the ventilation path L will be described furtherbelow.

FIGS. 3A and 3B show the finished pressure compensation label 10 fromabove, i.e. as a top view of the outside 2 a of the upper, i.e. secondfilm 2. The membrane film does not reach all the way to the outsideedges of the films 1, 2, but rather is at a distance from these,preferably by at least 1.0 mm, in each instance. However, the outercontour of the first film 1 as well as of the second film 2 (and therebyalso of the label 10 as a whole) does not have to be square, as shown.

FIG. 3A shows the top 2 a of the second film 2 in the event that inFIGS. 1A or 2A, the outer edge of the first film 1 is provided by R1,i.e. lies laterally outside of the outer ends 12 of the ventilationchannels 7. FIG. 3B, in contrast, shows the top 2 a of the second film 2in the event that in FIGS. 1A and 2A, the outer edge of the first film 1is provided by R1′ and the ventilation channels 7 end at the outer edgeR1′ of the first film 1.

The figures shown in FIGS. 3A and 3B therefore show the top of therespective finished pressure compensation label 10. The outer contour ofthe second film 2 corresponds, in FIGS. 3A and 3B, to those of the firstfilm 1. However, this is not necessary; in particular, the second filmcan be smaller, i.e. less expansive laterally than the first. On theunderside, the first film 1 is preferably adhesive over its full area.Preferably, it is also adhesive over its full area or covered with a topadhesive layer over its full area also on the top, i.e. toward thesecond film. The film is therefore adhesive over its full area on bothsides (this preferably holds true in connection with any desiredembodiment of this application), and this allows particularly simpleproduction from rolled material.

In FIG. 3A, it can be seen that the second film 2 has channel exitopenings 13 where the outer channel ends 12 of the ventilation channels7 lie underneath it, which openings connect the ventilation channels 7of the first film 1 with the outside surroundings of the pressurecompensation label 10 or of the housing provided with it. In FIG. 3A,the progression of only one of the four ventilation channels 7underneath the second film 2 is indicated with a broken line; theoutline of the membrane film 3 is shown likewise. The top of themembrane film 3 faces the second film 2. The recess 6 and the filmregions 8 that surround it, of the lower, i.e. first film 1, are coveredby the underside of the membrane film 3. As a result, the recess 6 iscovered in moisture-tight but air-permeable manner from above, therebyallowing the desired pressure compensation, but protecting the interiorof the article against penetrating moisture. Aside from the channel exitopenings 13, the second film 2 is configured to have a full area, i.e.it is free of other openings, interruptions or recesses.

According to FIG. 3B, the second film 2 actually does not possess anykind of recesses, because there, the outer ends 12 of the ventilationchannels 7, which coincide with the outer edge R1′ of the lower, firstfilm 1, simultaneously form the channel exit openings of the pressurecompensation label 10 as a whole.

In the pressure compensation label 10, the ventilation path thereforeleads from the outside through the ventilation channels 7 in the lower,i.e. first film 1, from their inner ends 11 further to the center of thesurface of the label—specifically at the level between the top of themembrane film 3 and the underside of the second film 2—and from there,finally, through the membrane and the recess 6 and afterward into thelabeled article. The region of the surface overlap of the membrane film3 with the second film 2 is configured to be non-adhesive. Preferably,the entire second film 2 is non-adhesive; neither on the top nor on theunderside.

Because the membrane film 3 over which the second film 2 is adhesivelyaffixed represents an elevation relative to the first film 1, the secondfilm arches up slightly over the membrane film 3. Furthermore—even inthe case of an adhesive top 1 a of the first film 1 over its fullarea—no adhesive connection of the first film with the second film,reaching all the way to the outer edge of the membrane film 3, isimplemented, due to the layer thickness of the membrane film 3. Instead,the surface region designated in this application as a “contact surfaceregion”, in which the first and the second film 1, 2 lie directly one ontop of the other (and are separated from one another, at most, by a thinadhesive layer having a constant layer thickness), does run around themembrane film 3, but is at a distance, in the lateral direction, fromthe outer edge of the membrane film 3 (because of the height differencebetween the membrane film 3 and the first film 1). This lateral distanceof the contact surface region of the films 1, 2 from the membrane film 3represents the ventilation path in the region between the inner ends 11of the ventilation channels 7 of the first film 1 and the top 3 a of themembrane 3 (more precisely: the interstice between the top 3 a of themembrane film 3 and the underside of the second film 2). From there, theventilation path continues further through the membrane film 3 andthrough the recess 6 of the first film 1, all the way to the pressurecompensation opening of the housing to which the label 10 is adhesivelyaffixed. Depending on whether excess pressure or partial vacuum tends toprevail in the housing to which the label is adhesively attached, airflows through the pressure compensation label 10 out of the housingprovided with it or into the housing.

FIGS. 4A and 4B show two alternative modifications relating to FIG. 3A,with regard to the configuration of the channel exit openings 13 in thesecond film 2, the top 2 a of which is also shown in FIGS. 4A and 4B.While the channel exit openings 13 are permitted in the form of circularor other kinds of recesses in FIG. 3A, for example, according to FIG. 4Amerely slot-shaped perforations of the second film 2, for example in theform of inner punched regions, are provided as channel exit openings 13.The inner punched regions are preferably curve-shaped or convolute, forexample semicircular, V-shaped, U-shaped or structured in some otherway. FIG. 4B shows a modification in which the channel exit openings 13are implemented by means of tabs that have been bent upward or at leastcan be bent upward. For this purpose, for example, a punched region isprovided as in FIG. 4A (if necessary with an additional bending line,which is represented with a broken line in FIG. 4B), and bent upwardwithin the scope of the production process, to form a semicircular tab,for example. The precise shape of the punched region or tab in FIGS. 4Aand 4B is shown merely as an example. Using such slot-shaped innerpunched regions or punched lines (FIG. 4A) and/or tabs bent up only by acertain angle (FIG. 4B), the outer end 12 of the respective ventilationchannel 7 of the first film 1, situated under the channel exit opening13, is less severely exposed to external influences such as ahigh-pressure washer or a steam-jet degreaser, for example.

FIGS. 5A and 5B show exemplary cross-sectional views of an article 20,for example a housing 25, provided with a pressure compensation label 10according to this application. In each instance, only a housing wall 26and a part of the interior 27 of the housing situated behind it areshown. The pressure compensation label 10 is situated on the outside oron the outer surface 30 of the housing wall 26, specifically in asuitable position for closing off the pressure compensation opening 40of the housing 25 or its housing wall 26 in air-permeable butmoisture-impermeable manner. For this purpose, the pressure compensationlabel 10 in FIGS. 5A and 5B is adhesively affixed to the surface 30 insuch a manner, in each instance, that the recess 6 of the first film 1comes into coverage with the pressure compensation opening 40 of thehousing 25 or of the other type of article 20. As a result, the pressurecompensation opening 40 is covered by that part of the underside 3 b ofthe membrane film 3 that spans the recess 6 of the first film and isadhesively affixed to the film regions 8 all around. The membrane 3 ispermeable for gases, particularly air; on its top 3 a, the furtherventilation path L first leads in the lateral direction beyond the edgeof the membrane film 3, and from there into the respective ventilationchannel 7 of the first film 1. To illustrate this ventilation path L,FIGS. 5A and 5B show a sectional view at the level of the recess 6 andof two ventilation channels 7, in each instance. With regard to theconfiguration of the outer end 12 of the ventilation channels 7, FIG. 5Ais based on FIG. 3B, according to which the ventilation channels 7 reachall the way to the outer edge R1′ of the first film and lead to theoutside laterally there. FIG. 5B, in contrast, is based on FIG. 3A inthis regard, according to which the outer ends 12 of the ventilationchannels 7 are at a distance from the outer edge R1 of the first film 1,and the second film 2 has channel exit openings 13 that lead to theoutside, above them. Of course, FIG. 5B can also be modified accordingto FIGS. 4A and 4B, and, of course, FIGS. 5A and 5B can be combined withany other figure or other embodiment of this application, with regard toall other details as well as combinations of characteristics. Forexample, the outer contour of the pressure compensation labels 10 inFIGS. 5A and 5B can assume any desired other shape instead of square,can have any other desired number of ventilation channels 7, and/or theouter contour of the membrane film 3 can be modified in any desiredmanner.

According to FIGS. 5A and 5B, the ventilation path L leads back into theplane of the first film 1 outside of the membrane film or outside of therecess 6 covered by it; the ventilation channels 7 of the film areseparated from the recess 6, in each instance, by the material bars orfilm regions 8 that serve as bridge regions. The film regions 8 therebyblock a direct passage between the recess 6 and each of the number ofventilation channels 7; the membrane film can therefore only be cross,but not circumvented.

In FIGS. 5A and 5B, the contact surface region or contact surface region9 can also be seen even better, in each instance; in this region, theupper, second film 2 lies on the top 1 a of the first film 1 with itsunderside 2 b. This contact surface region, in which the two films 1, 2touch one another (and are welded or glued to one another, for example),is situated exclusively outside of the base surface of the membrane film3 and furthermore only takes up a base surface, even outside of themembrane film 3, that is at a distance from the outer circumference ofthe membrane film 3. This holds true, in particular, in the region ofthe inner channel ends 11 of the ventilation channels 7, from where anunhindered air movement toward the center of the top of the membranefilm 3 must be guaranteed.

In the simplest case, as shown in FIGS. 5A and 5B, the height differencebetween the membrane film 3 and the first film 1 is utilized toguarantee a sufficient distance (all around the membrane film 3) betweenthe membrane film 3 and the contact surface region 9, i.e. theconnection region between the films 1 and 2. The lateral distance thatexists between the contact surface region 9 and the membrane film 3makes it possible for air that gets through the membrane film into theinterstice between it and the second film 2 can flow further all the wayto the inner channel end 11 of the respective ventilation channel 7 andfrom there through the channel to the outside. In order to guarantee asufficient cross-section of the ventilation path L in the region of theinner channel end 11 of the ventilation channels 7, the thickness orlayer thickness of the membrane film 3 and/or its base surface, forexample, i.e. its outer contour, can be selected in suitable manner. Forexample, the membrane film 3 can have bulges 21 laterally outward inregions between two adjacent ventilation channels 7, in each instance,as shown in FIGS. 2B and 2C. But even in the case of a square cut pieceof the membrane film 3, the corner regions reach further outwardlaterally from the center point of the recess 6 than the edge centers ofthe membrane. For this reason, the outer edges of the membrane film 3shown in FIGS. 5A and 5B, which are shown on the left and on the rightin the plane of the drawing, are also not in direct contact with theunderside 2 b of the second film 2, but rather are at a distance from itin the upward direction. The layer thicknesses of the first and secondfilm as well as of the membrane film are represented in exaggeratedlylarge manner in FIGS. 5A and 5B, so that they can be seen better; thelayer thicknesses and layer thickness ratios are not to scale. They canbe selected in suitable manner, particularly in order to guaranteesufficient center arch of the second film 2 above the membrane film 3,for example by means of the layer thickness of the membrane film 3alone. But the membrane base surface can also be configured in suitablemanner by means of the geometry or base surface shape of the membranefilm 3, for example with bulges 21 as in FIG. 2B, along the diagonaldirections between two ventilation channels 7, in each instance.

For further expansion of the ventilation path L between the ventilationchannels 7 and the interstice above the membrane top 3 a, an additionalspacer 14 can be applied to the membrane film 3, as shown in FIGS. 6Aand 6B. Thus, FIG. 6A shows a material ply 15, for example, which coversat least the membrane film 3 and, optionally, also the inner ends 11 ofthe ventilation channels 7. The material ply 15 itself is air-permeableand represents a nonwoven or other kind of woven fabric, for example. Itserves as a spacer 14 between the membrane film 3 and the second film 2(which must still be adhesively affixed to the arrangement in FIG. 6A,in order to obtain the finished pressure compensation label 10). Withregard to the outer ends 12 of the ventilation channels 7, FIG. 6A (andFIG. 6B for the case of a circular label) is based on FIG. 3B, by theway; i.e. the second film 2 is configured without any openings,punch-outs or other interruptions.

In FIGS. 6A and 6B, the outer regions of the first film 1, which areseparated by the channels 7 and cohesive only by way of the film regionsor bridge regions 8 (cf. FIGS. 1A, 2A), can be seen even betterindividually; the same holds true for FIG. 6B. While the spacer 14 isshaped to be square in FIG. 6A, according to FIG. 6B it possesseslateral bulges 21 (and between them, constrictions 22) having a similarshape as in the case of the membrane film 3 in FIG. 2B. Furthermore, notonly the membrane film 3 but also the spacer 14 can possess the samebase surface or outer contour; if applicable, with these or similarbulges 21. The spacer according to FIG. 6A or 6B increases the size ofthe up-arch of the second film 2 over the membrane 3 and, above all, atthe regions of the first film 1 that border on the latter, and therebybrings about the result that the inner ends 11 of the ventilationchannels 7 become more easily accessible from the center of the label,from the center of the label. In this regard, the air can also flowthrough the woven fabric (nonwoven, etc.) of the material ply 15 thatserves as the spacer 14, also in the lateral direction. Furthermore, amembrane film 3 can be used, which is already covered and connected witha nonwoven ply or another type of air-permeable material ply on oneside. Because of the greater up-arch of the second film 2, the inneredge 29 of the contact surface region 9 is clearly at a greater distancefrom the membrane 3 or the label center in the radial direction orlateral direction, as shown as an example in FIG. 6B; the ventilationpath within the label has widened. The upper, second film 2 is not yetshown in FIG. 6B, but is to be applied to the arrangement shown in FIG.6B from above during completion of the label, for example by means oflaminating it on. Afterward, the second film 2 then lies directly on thefirst film 1 only in an edge region (in this embodiment, anapproximately circular region), namely the contact surface region 9.

FIG. 7 shows a schematic cross-sectional view of an embodiment modifiedslightly as compared with FIG. 6A or 6B. According to FIG. 7, as in FIG.6A or 6B, an additional material ply 15 or a spacer 14 is provided onthe membrane film 3. As a result, the center up-arch or center arch ofthe second film 2 over the membrane film 3 is increased, and therebytheir reciprocal vertical distance from one another is increased. An airmovement or air transport in the material of the material ply 15 (anonwoven, felt, cloth or other woven fabric) in the lateral direction iseven more strongly possible than in the case of the membrane 3, withinthis material. The material ply 15 therefore does not represent anybarrier for pressure compensation, but rather increases thecross-section of the ventilation path. As compared with FIG. 6A or 6B,the modification in FIG. 7 consists in that the spacer 14 possesses thesame base surface as the membrane film 3. However, the representation inFIG. 7 was selected in such a manner that the recess 6 does but theventilation channels 7 do not lie in the drawing plane. For example, thedrawing plane in FIG. 7 runs diagonally through the top view of FIG. 6Aor 6B. As in FIG. 6A or 6B, the spacer 14 can possess a different,particularly a larger base surface than the membrane 3. Furthermore, themembrane 3 is not supposed to cover the inner channel ends 11 of theventilation channels 7 in the first film 1. In contrast, it is notharmful if they are covered by the air-permeable material of the spacer14. Preferably, the spacer 14 (or the membrane or both of them)possesses lateral bulges 21 in regions between the ventilation channels,for example similar to the cloverleaf-like outline structure of FIGS.2B, 6B or 2C. Because of the section plane in FIG. 7, which is rotatedby 45°, the ventilation channels 7 cannot be seen there. In turn, thecontact surface region or contact surface region indicated with thereference symbol 9 in FIGS. 5A and 5B can be seen even better in FIG. 7,as a boundary surface between the two films 1, 2 (shown cross-hatched inFIG. 7, in each instance). In the central label region, a great distancebetween the films 2 and 3 and thereby also a greater lateral distancebetween the outer edge of the membrane film 3 and the inner edge 29 ofthe contact surface region 9 (see also FIG. 6B) can be achieved by meansof the spacer 14, i.e. an easier or faster air flow or pressurecompensation can be achieved. The outer ends of the ventilation channelsthat cannot be seen in FIG. 7, due to the orientation, can optionally beselected in accordance with the alternatives of FIGS. 3A or 3B; i.e. thechannels can be guided to the outside toward the side or, alternatively,through the second film 2. Furthermore, adhesive layers on both sides ofthe first film 1, having the reference symbols 4 and 5, are alsoindicated in FIG. 7. Preferably, the first film 1 is a film that isadhesive on both sides, over its full area, i.e. already provided withadhesive layers 4 and 5, respectively. The first film 1 is adhesivelyaffixed to the surface 30 of an article 20, for example a housing 25,when the finished pressure compensation label 10 is dispensed, by meansof the underside adhesive layer 5, wherein the recess 6 covered by themembrane 3 comes to lie above the pressure compensation opening 40 ofthe housing wall 26. At the same time, the ventilation channels 7 in thefirst film 1 of the pressure compensation label 10, which have been opendownward until then, are closed off from below, namely by means of theadhesively covered surface 30 of the article itself. A separate,additional film for closing the channels from below or for formingventilation channels between the first and the second film is thereforeno longer required. The pressure compensation labels 10 according tothis application are therefore mechanically particularly robust, but atthe same time also very simple and cost-advantageous in terms of theirproduction.

The second film 2 in FIG. 7 (like in the other figures, as well) is afilm that is non-adhesive on both sides. The adhesive layer 4 istherefore a top adhesive layer of the first film 1. Instead of beingprovided over the full area, it could also be provided merely in certainregions, in some surface regions of the first film 1.

FIGS. 8A and 8B show two exemplary embodiments with regard to the shapeof the second film 2, which can also be transferred to all the otherfigures of this application. According to FIG. 8A, the second film 2 isa composite film 19, which has two or even more sub-layers 18, forexample. In the region above the ventilation channels 7, particularlyabove their inner channel end 11, a lower sub-layer 18 of the secondcomposite film 19 can be omitted, i.e. the second film can be thinnerthere, in order to widen the ventilation path located there. Also, twoof three sub-layers 18 can be provided with corresponding recesses 17,which can have different widths, if applicable. According to FIG. 8B, anupward arch 16 over the respective ventilation channel 7, particularlyits inner channel end 11, can also be present in the second film 2, inone or more sub-layers, instead of such recesses 17. Such upward arches16 can be produced, for example, by means of embossing the second film2, by means of die-cutting or slitting and/or bending, approximately inthe form that the second film is raised upward in roof-like orgutter-like manner along the surface regions in which the first film 1has the ventilation channels 7.

The upward arches indicated according to FIG. 8B are shown, in FIG. 9,in the top view of the top 2 a of the second film 2; their positionscorrespond to those of the ventilation channels 7 of the first film 1.These upward arches 16 are configured more or less locally in comparisonwith the relatively large-area up-arch of the second film, in total, inits central region, where it is pressed upward by the membrane film 3and, if applicable, also by the material ply 15 that serves as thespacer 14, during lamination.

By the way, to the extent that this application shows square orotherwise rectangular base surfaces of pressure compensation labels 10or their films 1, 2, the ventilation channels 7 of the first film and/orupward arches 16 or underside recesses 17 of the second film 2 can,alternatively, also run in the direction of the diagonal of therespective base surface. The ventilation channels 7 then extend all theway into the corners of the base surface or at least close to it, whilein the region of the edge centers of the base surface, less filmmaterial (particularly of the second film) accrues, which material couldoppose the respective bending caused by the up-arches and upward archesduring lamination.

Furthermore, the spacer itself can also be embossed into the upper,second film during lamination, i.e. when the first and the second film1, 2 are pressed together. During lamination or pressing of the twoouter films 1 and 2 against one another, channel exit openings 13, asshown in FIGS. 3A, 4A, and 4B, can furthermore also be pushed upright,pressed upright, or set upright into a specific angle position (forexample 45° relative to the film plane in FIG. 4B). For this purpose,suitable mandrels or projections of a pressing tool can be pressedupward under the channel exit openings 13 (not shown). Furthermore, thematerial for the spacer 14 or for the material ply 15 (nonwoven, felt,cloth, woven fabric, etc.) is selected in such a manner that sufficientair transport or sufficiently great gas permeability for effectivepressure compensation is guaranteed—also and specifically in the lateraldirection laterally through the nonwoven. At the same time, the materialis selected in such a manner that it is not excessively compressed whenit is pressed together with the second film 2.

FIG. 10 schematically shows an article 20 that is provided with apressure compensation label 10 according to any desired embodiment ofthis application. The label 10 is adhesively affixed over a surface 30of the article 20, in the region around a pressure compensation opening40. As a result, air exchange between the interior of the article 20 andthe surroundings is possible. The article is, for example, a housing 25or comprises such a housing. The article is, for example, a system, adevice, an individual part or an electrical or electronic component 24,particularly for a machine or for a vehicle or some other means oftransport. The article, as an electrical or electronic component 24, canhave a circuit board, an electrical or electronic part and/or some otherunit that consumes electrical power, for example.

FIG. 11, in an enlarged representation, shows the label 10 that has beenadhesively affixed to the article in FIG. 10; it is configured asdescribed below, using FIG. 11, for example, or alternatively,structured according to any other embodiment of this application.According to FIG. 11, the ventilation channels 7, along which airtransport in the label 10 takes place in the lateral, i.e. lateraldirection (parallel to the surface 30 of the housing wall 26), in thediagonal direction with reference to the edges of the label basesurface, which is rectangular here. Optionally, the label surface isextended in one direction (downward in FIG. 11), i.e. it gets fartheraway from the recess 6 for the pressure compensation opening 40 alongthis direction than in the opposite direction and in the lateraldirections perpendicular to it. In this way, an inscription 23 (forexample by means of screen printing) can be additionally accommodated,for example, and the label can be used not just as a pressurecompensation label 10 but also as a nameplate or for some otheridentification of the article 20. The alphanumeric or other inscription23 is preferably situated laterally outside of the membrane film 3, i.e.it is disposed without overlap relative to the membrane film 3 and—ifthe pressure compensation label has a material ply 15 that serves as aspacer 14—also without overlap relative to the material ply 15.

If the pressure compensation label 10 is supposed to have the outerchannel outlets for the ventilation channels 7 laterally at the labeledge or on the label edge surface, according to any desired figure orother embodiment of this application (instead of on the top of thesecond film), then—regardless of the final label outline—the surface ofthe film webs for the first and second films 1, 2 can be selected, atfirst, to be larger than actually necessary for the label surface, andthe label edge can first be punched outside of the range of theventilation channels 7, for example in accordance with the outer edge R1or R2 in FIGS. 1A, 1B, 2A or 2B. Subsequently, the label surface can bereduced in size by means of a (if necessary repeated) punching process,for example in accordance with the edge R1′ or R2′ (shown with a brokenline in FIGS. 1A, 1B, 2A, 2B, and also underlying FIGS. 3B, 6A, 6B). Inthis way, the ventilation channels 7 are punched at their outer ends 12and thereby opened toward the side, wherein the surrounding edge dropsaway (bled-off punching).

FIG. 12 shows an alternative embodiment to FIG. 9, in which the upwardarches 16 (FIG. 8B), in contrast to FIG. 9, run not just along theventilation channels, above them, but rather are also configured overthe central region of the film 2 that covers the membrane film; theyextend all the way to the film center and meet one another there. Thefilm 2 therefore has an upward arch 16, which is configured at leastalso in the central region of the second film 2 (i.e. in the surfaceregion above the membrane film 3), and extends all the way to thesurface regions above the ventilation channels 7, specifically at leastall the way to over their inner ends 11. In the central region of thesecond film 2, a widened upward arch 16′ or a widened region of it canbe configured, for example.

Any upward arches 16 or 16′ according to one of FIG. 8B, 9 or 12 can becombined with any desired other figure or embodiment of thisapplication. The upward arches 16 or 16′ are preferably film regionsformed to stand out by means of embossing, i.e. the project upward onthe top 2 a of the second film 2 (embossed film). Instead of upwardarches 16 or 16′ formed by means of embossing, according to FIG. 8B, 9or 12, such elevations in certain regions, relative to the first film 1,can alternatively be implemented also by means of underside gaps 17 inone or more sub-layers 18 of the second film 2 (composite film 19),approximately as already shown in FIG. 8A. In particular, gaps 17disposed on the underside 2 b of the composite film 19 can have anoutline and/or a surface expanse as explained in FIG. 12, using theupward arches 16.

The overhangs 28 shown in FIG. 13 (as well as the correspondingoverhangs 28 in the subsequent FIGS. 15 and 17) of the membrane film3—and optionally also of the material ply 15—beyond the inner ends 11 ofthe ventilation channels 7 do cover these inner ends, i.e. prevent theiruse for air transport for pressure compensation. The advantage of thismembrane having larger dimensions, which has surface regions that serveas overhangs, consists, however, in that a (tolerance-related, notentirely avoidable during production) lateral offset of the membranefilm can no longer lead to the result that any one of the ventilationchannels 7 is unintentionally completely covered by the second film. Theoverhangs 28 therefore prevent the inner edge 29 of the contact surfaceregion 9 from coming to lie closer to the surface center of the label,at any one of the ventilation channels 7, than the innermost end 11 ofthe ventilation channel 7 in question, thereby blocking this ventilationchannel in question and making it ineffective.

FIGS. 13 to 17 therefore show further exemplary embodiments relating toimproved positioning of the course of the inner edge 29 of the contactsurface region or contact surface region 9 (between the first film 1 andthe second film 2). Within the inner edge 29 of the contact surfaceregion 9 between the films 1, 2, the further ventilation pathspecifically runs in the interstice between them; the ventilationchannels 7 are extended all the way to the label center (above themembrane film 3) by means of this path. Of course, the examples of FIGS.13 to 17 can optionally be combined with closed R1 or R2 or open outerfilm edges R1′ or R2′. They can also be optionally implemented with orwithout (optional) spacers 14 or the material ply 15 used for them.Furthermore, outline, size and/or shape of all the films 1, 2, 3 as wellas the number of ventilation channels 7 can be varied. Correspondingmodifications are also conceivable for the exemplary embodiments ofFIGS. 1A to 12.

FIG. 13, in concrete terms, shows an alternative embodiment to FIG. 2C,wherein now, the membrane film 3 forms a respective overhang 28 beyondthe inner end of each ventilation channel 7. The membrane film (shownwith cross-hatching) is square or rectangular, for example; in any case,it covers the inner ends 11 of the ventilation channels 7. Furthermore,the contact surface region 9 between the first film 1 and the secondfilm 2 can be seen, along with its inner edge 29 (shown with a brokenline), which encloses the air volume that forms the further ventilationpath between the films 1 and 2 (or 3 and 2 above the membrane). As canbe seen in FIG. 13, this inner edge 29 does reach relatively close tothe outer edge of the membrane film 3, but is still at a sufficientdistance from it so that air can flow between the outer membrane edgeand the inner edge 29 of the contact surface region 9, down into theventilation channels 7 of the first film 1 (or—in the oppositedirection—can flow from there upward beyond the edge of the membranefilm all the way to the membrane top 3 a). This lateral distance (allaround the membrane film) between the outer membrane edge and the inneredge 29 of the contact surface region 9 does turn out to be relativeslight in FIG. 13 (e.g. as the result of a low membrane thickness orlayer thickness), but is sufficiently great so as not to interrupt theventilation path between the ventilation channels 7. Such a distancebetween the outer membrane edge and the inner edge 29 of the contactsurface region 9 is also present in the other exemplary embodiments(particularly those of FIGS. 2A to 7 and 11), even if this distance isshown in the drawing only in FIG. 6B (and was shown significantly largerthere, solely because of the layer thickness that is increased in sizerelative to the membrane by the spacer 14 there (cf. the position of thereference symbol 29 in FIG. 6B).

FIG. 14 shows a schematic view that supplements FIG. 2A, in which thecontact surface region 9 and its inner edge 29 (shown with a brokenline) can additionally be seen. The membrane film 3 once againreaches—actually—so far toward the inner end 11 of each ventilationchannel 7 that the inner edge 29 of the contact surface region 9 of thetwo films 1, 2 lies further outward than the inner end 11 of theventilation channel 7 in question (during the production step oflamination or pressing together of the two films 1, 2 that is used). Inthe case of tolerance-related incorrect positioning of the membranefilm, however, one or more ventilation channels 7 could also beunintentionally closed at their inner end 11).

FIG. 15 shows an alternative embodiment with regard to FIGS. 2A and 14,in which the risk of such channel closure is reduced in that themembrane film has overhangs 28 beyond the inner end 11 of each of theventilation channels 7. The inner edge 29 of the contact surface region9 lies farther outside in comparison with FIG. 14.

FIG. 16 shows a supplemental schematic view relating to FIG. 2B—onceagain with the additional representation of the contact surface region 9and its inner edge 29. In contrast to FIG. 6B, this edge liessignificantly closer to the outer edge of the membrane—either becausehere, the spacer 14 is missing, or because the membrane 3 and the spacer14 (having the same or a deviating contour in comparison with themembrane) possess less layer thicknesses than in FIG. 6B. Although themembrane 3 and/or the spacer 14 are provided with lateral bulges 21 andenclose the inner ends 11 of the ventilation channels 7 in U shape (aswas already the case in FIG. 2B, 2C or 6B), a certain risk of individualchannel closures could still exist in the case of an offset of themembrane and/or of the spacer 14.

FIG. 17 therefore shows an embodiment modified as compared with FIGS. 2Band 16, in which—in addition to the lateral bulges 21 of the membrane 3and/or of the spacer 14—the membrane 3 and/or the spacer 14 furthermorealso have surface regions above the inner end 11 of each of theventilation channels 7, which serve as an overhang 28. Here, theoverhangs 28 are represented as straight edge regions; as compared withFIG. 16, they represent a shortening of the constrictions 22 between theadjacent bulges 21.

According to FIGS. 16 and 17, the inner edge 29 of the contact surfaceregion 9, shown with a broken line, is sufficiently spaced apart fromthe inner ends 11 of the ventilation channels 7 on all sides, in thecase of a correct position of the membrane film 3 and/or of the spacer14; specifically because of the bulges 21. Only in the case of aparticularly low layer thickness of the membrane and/or of the spacer 14could the inner edge 29 of the contact surface region 9 come to liedangerously close to the inner channel end 11, between adjacent bulges21—as shown as an example in FIG. 17, by the dotted (instead ofbroken-line) inner edge 29′ on the left and lower ventilation channel7—and then can close off this channel, as soon as the incorrectpositioning of the membrane film exceeds a certain tolerance value. Eventhen, however, thanks to the overhangs 28 of the membrane (and,alternatively or in addition due to the overhangs of the spacer 14), itis guaranteed that none of the inner channel ends 11 is closed off.

FIG. 18 schematically shows an exemplary embodiment with regard to amethod for the production of a plurality of pressure compensation labels10. In this method, first a material web I is processed, the structureof which is shown in FIG. 18, top left, on an enlarged scale. Thematerial web I comprises a first film web 101, a first adhesiveprotection film 31, and a second adhesive protection film 32. The firstfilm web 101 has an adhesive layer on the top and on the underside, i.e.it is adhesive on both sides. According to FIG. 18, for example, thefirst adhesive protection film 31 is disposed on the top adhesive layer,and the second adhesive protection film 32 is disposed on the undersideadhesive layer. Silicone-coated polymer films or silicone-coated paper,for example serve as adhesive protection layers 31, 32 (see also theexplanations relating to FIGS. 1A to 1C). The first film web 101,adhesive on both sides, disposed between the first adhesive protectionfilm 31 and the second adhesive protection film 32, serves as thestarting material for the production of the first film 1 for a pluralityof pressure compensation labels 10 to be produced. In FIG. 18, the topand underside adhesive layer of the first film web 101 are representedas cross-hatched regions close to the two adhesive protection films 31,32.

The material web I can be present, for example, in the form of manysheets or, as shown in FIG. 18, as rolled material. Thus, for example, acoil S1 of this material web I is unwound to carry out the methoddescribed below, i.e. this material web is unrolled from the coil S1(reference symbol A).

First, in step a) of the method, the recesses 6 and ventilation channels7 for the labels are punched into the material web I by means of asuitable punch. The punching process is carried out in such a mannerthat the second adhesive protection film 32 (the underside adhesiveprotection film in FIG. 18, for example) remains intact and the outlinesof the recesses 6 and ventilation channels 7 are punched only throughthe layers of the first adhesive protection film 31 and of the firstfilm web 101 (reference symbol B). Subsequently, in step b) (referencesymbol C), the second adhesive protection film 32 is pulled off orunrolled. In this regard, the pieces of the first film web 101 and ofthe first adhesive protection film 31 situated within the punchedoutlines at first remain adhering to the second adhesive protection film32, i.e. are pulled off or lifted off together with the latter. In stepc), another, third adhesive protection film 33 is pressed onto oradhesively affixed onto the side of the first film web 101 that has beenexposed in this manner (reference symbol D). Finally, in step d), theopposite, first adhesive protection film 31 is lifted off or pulled off(reference symbol E). Steps c) and d) can also be carried outsimultaneously (in FIG. 18, directly one on top of the other on the samepiece of the film web 101 then, in each instance).

At this point, it should be pointed out that the method steps here aredescribed in the specific sequence in which they are carried out, oneafter the other, on a concrete, small piece of the first film web 101,in each instance. The entire method, however, can be carried out as anendless process, wherein new material of the film web 101 iscontinuously supplied and processed, specifically with all method stepsat the same time. In this regard, the listing of the method steps shouldnot be understood in the sense of a strict sequence, at least withreference to the material ply I or with reference to the film web 101.

The one side (in FIG. 18, the underside) of the material web is now onceagain covered with a full-area adhesive protection film 33, whereas theother side (in FIG. 18, the top) of the first film web 101 is nowexposed and has not only punched contours but rather real recesses 6 andventilation channels 7, which are exposed on the adhesive side. Now, instep e), a plurality of individual membrane films 3 is adhesivelyaffixed over the recesses 6. In this regard, the film regions thatseparate the ventilation channels 7 from the recesses 6 are also coveredadhesively. Supply and application of the membrane films 3 (referencesymbol F) takes place by means of a suitably automated unit or machine,which divides a continuous membrane film web (not shown) into filmpieces of membrane films 3, having the same size, for example, transfersthese pieces to a roll and/or to a conveyor belt at predefined,identical intervals, and from there then positions the above therecesses 6 of the top adhesive first film web 101 and presses them down,in a precise position. In similar manner a plurality of individualspacers 14 can—optionally—be supplied and applied in a subsequent methodstep (reference symbol G); these spacers serve as an additional materialply 15 between the membrane films 3 and the second film web 102, whichis still to be applied.

Finally, in step f), the second film web 102 is applied to the materialweb that has been prepared in this manner (from the side of the membranefilm 3 or the exposed, adhesive side of the first film web 1) (referencesymbol H). In this way, a processed material web II is formed as anendless web. This can we wound up onto a further coil S2 for later use,or can also be processed further immediately, to produce pressurecompensation labels 10. For the latter, the only thing still required isto punch the ultimate pressure compensation labels 10 out of thematerial web II. This can be done by means of a punching process (notshown, but can be carried out between H and S2 in FIG. 18), in which thefirst and the second film web 101, 102 are severed and thereby aplurality of pressure compensation labels 10, as described in thisapplication, are formed. Each of these labels 10 has precisely onerecess for being adhesively affixed over a pressure compensation opening40, as well as one or more ventilation channels 7. During this punchingprocess, the outer edge of the pressure compensation labels 10 ispunched, i.e. (depending on the embodiment of the preceding figures),the edges R1 and R2 or, alternatively, the edges R1′ and R2′. In thisregard, both film webs 101, 102 are punched through at the same time orby means of the same method step, in every case, so that complete,finished labels are produced.

During this process, the third adhesive protection film 33 can also bepunched at the same time, or, alternatively, can also be left intact, sothat the pressure compensation labels 10 continue to remain adhering tothe third adhesive protection film as the ultimate carrier film. Thegrid can still be pulled off around the individual labels; rolledmaterial containing pressure compensation labels 10, ready for shipping,is formed; these labels have a very simple structure and are produced invery cost-advantageous manner, and particularly make do with fewer filmlayers than conventional labels.

As can be seen from FIG. 18, the entire method can be carried out in asingle operation, even though it comprises a plurality of method steps,which operation can actually be carried out continuously, i.e. for theuse of a single, continuously supplied material web that is processedfurther. This is not known from conventional pressure compensationlabels or their production methods; usually, a membrane label, in otherwords the actual adhesive ventilation element, and the upper protectivelabel have to be produced separately from one another, and these twolabel parts must then be pressed onto one another, with precise fit.Conventionally and regularly, two separate material webs must first bepre-processed for this purpose, before they can be joined together toform a uniform material web in a later method step (if necessary aftercorresponding remounting or intermediate storage). Accordingly, as manyas three passes of material webs through respective processing lines areactually required conventionally, in order to obtain finished pressurecompensation labels 10. In the method according to the presentapplication, however, a single pass of a material web is sufficient toproduce a plurality of finished pressure compensation labels 10—actuallyalready pre-assembled as rolled material ready for sale.

REFERENCE SYMBOL LIST

-   1 first film-   1 a top-   1 b underside-   2 second film-   2 a top-   2 b underside-   3 membrane film-   3 a top-   3 b underside-   4, 5 adhesive layer-   6 recess-   7 ventilation channel-   8 film region-   9 contact surface region-   10 pressure compensation label-   11 inner end-   12 outer end-   13 channel exit opening-   14 spacer-   15 material ply-   16; 16′ upward arch-   17 gap-   18 sub-layer-   19 composite film-   20 article-   21 bulge-   22 constriction-   23 inscription-   24 component-   25 housing-   26 housing wall-   27 interior-   28 overhang-   29; 29′ inner edge-   30 surface-   31 first adhesive protection film-   32 second adhesive protection film-   33 third adhesive protection film-   40 pressure compensation opening-   101 first film web-   102 second film web-   A, B, . . . H processing step-   d1 layer thickness-   I, II material web-   L ventilation path-   R1, R1′; R2, R2′ outer edge-   S1, S2 coil

1. Pressure compensation label (10) for adhesive affixation to a surfaceof a housing or of another article provided with a pressure compensationopening, wherein the pressure compensation label (10) has the following:a first film (1) for adhesive affixation to a surface provided with apressure compensation opening, an outer, second film (2), and anair-permeable membrane film (3), which is disposed between the firstfilm (1) and the second film (2), wherein the first film (1) has arecess (6) intended for positioning above a pressure compensationopening, as well as a number of ventilation channels (7), and whereineach of the ventilation channels (7) is separated from the recess (6) bya film region (8) of the first film (1), wherein the membrane film (3)covers the recess (6) and each of the film regions (8) between therecess (6) and the number of ventilation channels (7), and wherein theouter, second film extends laterally beyond the membrane film (3),covers the number of ventilation channels (7) of the first film (1) atleast in certain regions, outside of the membrane film (3), and spans aventilation path (L), which leads from the surface of the membrane film(3) that faces the second film (2) all the way to the number ofventilation channels (7) of the first film (1).
 2. Pressure compensationlabel according to claim 1, wherein the ventilation channel (7) is/arefurther recesses of the first film (1), at a distance from the recess(6).
 3. Pressure compensation label according to claim 1, wherein eachof the ventilation channels (7) leads out of the pressure compensationlabel (10) at an outer edge (R1′) of the first film (1).
 4. Pressurecompensation label according to claim 1, wherein the second film (2) hasa channel exit opening (13) above an outer end (12) of each of theventilation channels (7) of the first film (1), by means of which theventilation channel (7) is accessible, wherein the respective channelexit opening (13) is configured in the form of a recess, punch-through,die cut, bent-up film surface, cutting line or other type of opening. 5.Pressure compensation label according to claim 1, wherein the secondfilm (2) is connected with the film (1) and/or with an adhesive layer(4) disposed above it, in a contact surface region (9) situated outsideof the membrane film (3), and wherein each of the ventilation channels(7) is brought closer to the membrane than the contact surface region(9).
 6. Pressure compensation label according to claim 1, wherein thepressure compensation label (10) has an air-permeable spacer (14)between the membrane film (3) and the second film (2).
 7. Pressurecompensation label according to claim 6, wherein the spacer (14) is anair-permeable material ply (15) composed of a nonwoven, felt, cloth,woven fabric or some other type of air-permeable material. claim 8.Pressure compensation label according to claim 1, wherein the pressurecompensation label (10) has at least three ventilation channels (7) inthe first film (1), and wherein the membrane film (3) and/or the spacer(14) possesses recesses, constrictions (22) or at least a smallerlateral expanse in the direction of the ventilation channels than n bebetween adjacent ventilation channels (7).
 9. Pressure compensationlabel according to claim 1, wherein the first film (1) has two, three,four, six or some other multiple of ventilation channels (7), which aredisposed symmetrically around the recess (6) intended for the pressurecompensation opening.
 10. Pressure compensation label according to claim1, wherein the first film (1) is a film that is adhesive and wherein thesecond film (2) is adhesively affixed to the first film (1) in a contactsurface region (9) situated laterally outside of the membrane film (3).11. Pressure compensation label according to claim 1, wherein the secondfilm (2) has upward arches in surface regions above and/or close to theventilation channels (7) of the first film (1), for example in the formof embossings, flutings or bends, or underside gaps (17).
 12. Article(20) having a surface (30) that has at least one pressure compensationopening (40) wherein the at least one pressure compensation opening (40)is covered with a pressure compensation label (10) according to claim 1.13. Method for the production of pressure compensation labels (10), eachpressure compensation label (10) of which has the following: a firstfilm (1) that has a recess (6) intended for positioning above a pressurecompensation opening, and a number of separate ventilation channels (7),in each instance, a membrane film (3) that covers the recess (6), and asecond film (2) that extends laterally beyond the membrane film (3), andcovers the number of ventilation channels (7) laterally outside of themembrane film (3), at least in certain regions, wherein the membranefilm (3) is disposed between the first film (1) and the second film (2),wherein the method comprises: a) punching (B) the recesses (6) and theventilation channels (7) into a continuous first film web (101) that isadhesive on both sides, the two sides of which web are covered by afirst (31) and a second adhesive protection film (32), wherein the firstadhesive protection film (31) and the first film web (101) are punchedthrough, whereas the second adhesive protection film (32)remainsunpunched, b) removing (C) the unpunched second adhesive protection film(32) from the first film web (101) and, in this regard, removing (C)film pieces of the first film web (101) as well as film pieces of thefirst adhesive protection film (31) from the punched recesses (6) andventilation channels (7), in each instance, c) adhesively affixing (D) athird adhesive protection film (33) to the side of the first film web(101) that faces away from the first adhesive protection film (31), d)exposing the other side of the punched first film web (101) by removing(E) the first adhesive protection film (31) from the first film web(101), e) adhesively affixing (F) individual pieces of membrane films(3) to the exposed of the first film web (101), f) adhesively affixing(H) a second film web (102) to the side of the first film web (101)covered with the membrane films (3), and g) punching out a plurality ofpressure compensation labels (10) from the material web formed in thismanner, which encompasses the first film web (101) and the second filmweb (102).
 14. Method according to claim 13, wherein in step g), aplurality of first films (1) is punched from the first film web (101),and a plurality of second films (2) connected with the first films (1)is punched from the second film web (102).
 15. Method according to claim13, wherein between steps e) and f), a plurality of individual pieces ofan air-permeable material ply (15) is applied to the membrane films (3)and/or to the first material web (101).